Tubular steam boiler



Jan. 31,. 1933. M EULE TUBULAR STEAM ILER. I

Filed Nov. 14, 1929 5 Sheets-'Shee t 1 WWW 145/ runs M. EULE 1,895,790

' TUBULAR STEAM BOILER Filed Nov. 14, 1929 5 Sheets-Sheet 2 Jan. 31,1933.

Etkiub Sax II II WITNESS aw ww mww Jan. 31,1933. M. EULE 1,895,790

TUBULAR STEAM 3011mm Filed Nov. 14, '1929 5 Sheets-Sheet s gvwentoz''mmtul M M. EuLE- .TUBULAH STEAM BOILER Filed Nov. 14 1929 Jan. 31,1933;

5 Sheets-Sheet" 4 Jan. 31 1933.

M. EULE TUBULAR STEAM BOILER Filed Nov. 14. 1929 5 Sheets-Sheet 5awwemtoz bustion chamber,

Patented Jan. 31, 1933 UNITED STATES PATENT OFFICE MARTIN EULE, 0FBERLIN-SPANDAU, GERMANY, ASSIGNOR TO SIEMENS-SGHUGKERT- WERKEAKTIENGESELLSCHAFT, 0F BERLIN-SIEMENSSTADT, GERMANY, A COBYO- RATION 0FGERMANY Application. filed November 14, 1929, Serial No. 407,137, and

My invention relates to tubular steam generators and in particular tothe type of generator in which steam is produced at or near .criticalpressure and in which comparatively high temperatures are employedin thecomall of which features involve particular constructions different fromthose heretofore employed in the art.

The specific improvements involve first, the provision of a verticalboiler of polygonal outside contour, having a cylindrical combustionchamber in the first part, and a polygonal, specifically, rectangularcombustion chamber in the second part of the path of the flame, thewalls of both chamber portions being lined with steam generating tubes(which form respectively round and rectangular coils), whereby thesecoils form as it were the walls of the combustion chamber. Second, theprovision of a combustion chamber dome which is circumferentiallypartlybuilt up of generating tubes. Third,'the arrangement of the tube coilsin the form of multiple thread pipe coils, the individual threads beingdiscontinuous, i. e. interrupted at certain intervals at which theyterminate in common headers and auxiliary devices, to be described morefully hereinafter, for the purpose of mixing the operating mediumpassing through the individual tubes, and

for redistributing the medium uniformly among the subsequent threads,and for facilitating the blowing out of the individual tubes in order toremove the sludge and scale apt to collect during the operation. Fourth,the arrangement in such a steam generator of the steam generating tubesand the superheating tubes and the economizing tubes in such manner thatall steam generating tubes form the walls of the combustion chamber andreceive the heat originally produced in the chamber by radiation, thesuperheating tubes being grouped with respect to the combustion gasflow, so as to encounter directly the gases discharged from thecombustion chamber, and the economizing tubes being grouped so as toencounter directly the combustion gases after they have passed thesuperheating tubes.

TUBULAR STEAM BOILER in Germany March 14, 1929.

The accompanying drawings portray the arrangement of such a boiler.

In these drawings Figs. 1 and 1 combined show a longitudinal verticalsection through the boiler on the line 11 in Fig. 2, 1

Fig. 2 shows a horizontal section through the boiler on the broken line2-2 in Figs. 1, 1

Fig. 3 shows a flow diagram of the medium through the boiler.

Figs. 4 and 5 show a sludge and distributing valve (such as is indicatedin the flow diagram by the legends) in longitudinal vertical section intwo operating positions,

' Fig. 6 shows a horizontal section through the valve on the line 66 inFig. 4, and

Figs. 7 and 8 show in longitudinal vertical and in transverse sectionrespectively a suitable form of continuous sludge separator, indicatedin Fig. 3.

Referring to ture comprises in its lower portion a vertical wallstructure 1 which may be surrounded for heat insulating purposes by anair jacket 2 shown in detail in Fig. 2. This air jacket, for simplicityssake and in order to save space, has been omitted in Figs. 1 and 1 sinceit has no particular bearing on the novel features of the presentinvention. Within this outer wall structure is suspended the combustionchamber which contains the generating tubes in the following manner. Theupper portion of the chamber shown in Fig. 1 is cylindrically shaped andis formed by an iron cylinder 3 which issuspended from the roofstructure of the boiler, (not shown here) by means of cables 4. Ch theinner periphery of this cylinder are disposed the cylindrical tube coils5 spaced closely adjacent to each other, such that they virtually formthe immediate wall of the combustion chamber, thereby protecting theiron cylinder, to which the tubes are attached by suitable means knownin the art, and not shown here, sufficiently from the heat of radiationin the coinbustion chamber. These generating tubes 5 while spacedclosely adjacent to each other do not form a single coil but form amultiple Figs. 1 and 1 the boiler struc 7 apart as shown,

. be noted that this portion of the com threads having a considerablepitch such as is shown with respect to one sin le tube coil 6 in Fig. 1..The remaining tu s are only shown in cross-section so as not to obscurethe view. The cylindrical combustion chamber is closed at the top by adome which is partly formed by generating tubes 5 also arranged inmultiple thread fashion, as has ust been described, and fastened to ironplates 7 suspended from the roof structure a of the boiler biy means ofcables 8. The central portion 0 the dome is composed of refractorymaterial suspended from the superstructure, and in this refractory discthe nozzles 10 and 11 for the fuel and air are arranged. Thus, the heatis supplied in this particular boiler from the top.

A short. distance from the top secondary air nozzles 12 are provided inthe wall circumference of the combustion chamber. These nozzles arearranged in groups spaced and the generating tubes pass between thesegroups as shown in full lines with respect to.one single tube and indashdot lines with respect to some of the other tubes. At the point 13the entire group of tubes, coming from the top and forming the multiplethread coil, is interruptedinits path through the combustion chamber,and is led to a header outside of the combustion chamber. The detailarrangement of the header structure with respect to the boiler structureis immaterial. Its functional position will clearly appear from Fig. 3which will be shortly described.- At the point 13 in Fig. 1 only a fewof the group of coils coming from the top are shown for simplicityssake. One half of the upper portion of the cylindrical combustionchamber is shown at the left hand portion of the horizontal section,Fig. 2, and there some of the coils are shown leading to the outside atthe point 13.

The tubes reenter the combustion chamber at the point 14 closelyadjacent to 13 and continue forming the lower part of the combustionchamber which will now be described. Referring to the lower portion ofF1g. 1 and to Fig. 1 and Fig. 2, right hand side t Wlll bustion chamber.is substantially rectangular. It is formed by an outer wall of plate11'011 15 which is attached to the supporting structure 16 of the boilerhousing, this iron mantle carrying on its inner periphery the generatingtubes 5 in multiple thread coils slmilar to the manner which has beenexplained with reference to the upper cylindrical portion of the boiler.Here again only one single tube thread 6 is shown for clearness sake,and in order to portray the approximate pitch at which each of theindividual tube threads passes downward along the wall of the chamber.This rectangular combustion chamber extends down to the lower portion ofthe outchamber the tubes corresponding with the number passing throughthe they leave the combustion stantially to the point at which thisouter boiler structure is contracted to form a-funnel 17 at the bottomof which the ashes are collected and removed (not shown here). At thelower end of the rectangular combustion leave the chamber as shown atthe point 18 and are lead to another header and to auxiliary devices notshown in Fig. 1"", but which will appear from Fig. 3..

As will appear from Fig. 1 and from the right hand side of Fig. 2 aconsiderable space is provided between the iron walls 15 of therectangular combustion chamber, and the outer wall 1 of the lower boilerstructure. Within this space the superheater tubes 20 are disposed in aplurality of parallel groups of groups of generating tubes boiler, andbeing divided .if necessary into additional parallel groups amongthemselvesas expediency may dictate. This latter feature is not shown inthe drawings as being obvious and well known in the art. The essentialfeature according to the present invention is the arrangement of thesegroups of superheater tubes 20 in a space adjacent to the lower portionofthe combustion chamber, and at a point at which they are encountereddirectly by the combustion gases as chamber. The path of the combustiongases is indicated in Fig. 1 by the two curved arrows. These groups ofsuperheater coils extend only a small distance upward onv two oppositesides of the rectangular combustion chamber, so that they are located inthe hottest zone of the discharged combustion gases. The legends in Fi 1To superheater and From generator (at the point 22) indicate where thegenerating tubes leave the combustion chamber and where they enter thesuperheater groups. At the lower portion of the superheater chamber thesuperheater tubes leave the boiler and lead to the consumer. This pointis indicated in Fig. 1 by the legend To consumer. The particular chamberportion in which the superheater coils arelocated as indicated in Fig. 1and Fig. 2 with 25. The discharged combustion gases rise in thesuperheater chamber 25 and encounter in the upper portion 26 of thischamber groups of economizer tubes 27 in which the water delivered bythe feed pump is heated preliminary to its supply to the steamgenerating tubes. The upper ends of these economizer coils shown in Fig.1 receive the Water delivered by the feed pump and the lower ends ofthese coils discharge the water, as shown in the upper portion of Fig. 1by the legend To generator. With this latter legend corresponds thelegend appearing in the lower portion of. Fig. 1 From economizer whichpoints to the beginning of the steam generating tubes at the bottom ofthe combustion chamber into which the water discharged by the economizeris delivered in well heated condition.

The hot gases leaving the economizer space travel in the direction ofthe arrows in Fig. 1 and pass through the air preheaters 30 which arerepresented in Fig. 1; by three squares on diametrically opposite sidesof the cylindrical combustion chamberand which may be of any suitabletype known in the art. In Fig. 2 one of the air preheaters isdiagrammatically shown in section. It consists of a large group ofplates between which alternately combustion gases and combustion airpass. The details have been entirely omitted in this illustration andonly the portions of the preheater carrying combustion air have beenindicated with horizontal dashes, and those portions carrying combustiongases have been indicated with vertical dashes. The combustion gases arefinally discharged from the preheaters into the upper portion of theboiler structure, not shown here. The

combustion air which enters the preheaters at the top as shown by thecurved arrows in Fig. 1 leaves the lowermost air preheaters at the pointshown by the curved arrows and enters the spaces 31 between the airpreheaters and the cylindrical combustion chamber portion. These spacesare more clearly shown at the left hand portion of Fig. 2 and occupy thecorners formed by the outside boiler wall 1 and the superheaters and thecylindrical portion of the combustion chamber. The air rises in thesespaces and thereby protects the iron plate walls 3 of the cylindricalcombustion chamber against overheating by carrying the heat conveyed bythe boiler tubes away. Thus, the combustion air is simultaneouslyfurther heated before it is supplied to the burners. The combustion airenters the air supply ducts 32 which lead to the air supply nozzles. Thedetails of this arrangement are not'shown in the drawings as thesefeatures do not form part of, and. are not necessary for theunderstanding of the present invention. They are besides well known inthe prior art.

Referring now more particularly to Fig. 3 which represents the flowdiagram, it will be noted that the water supplied by the feed pumpenters the system at the left hand end indicated by the legend From feedpump. It first enters a main header so labeled, whence it is distributedover a number of sub-headers also thus labeled, and from thesesub-headers the water enters the economizer tub'es 27 located in theeconomizer chamber 26 shown in Fig. 1 Before'the water discharged by theeconomizer enters the generating coils as described hereinbefore, itpasses, as shown in Fig. 3, through a group 7 of sludge separatorsindicated in Fig. 3.

These valves will be described hereinafter in detail with reference toFigs. 4 to 6. The object of these valves is to selectively connect eachindividual economizer tube through a blow down valve, with a chamber oflow pressure, or with the outside atmosphere, and thus to blow out thecontent of one individual tube line togetherwith all sludge which may bedeposited therein. From sludge valves 60 the water passes into a sludgeseparator 61 of the continuously separating type, also to be describedin detail hereinafter with reference to Figs. 7 and 8, and thencethrough a number of headers into the steam generating'coils of theboiler at 18, the point in Fig. 1 labeled From economizer. Thegeneratingcoils in leaving the rectangular portion of the combustion chamber atthe point 14 in Fig. 1 enter outside of the boiler a number of sludgevalves 60 of the type aforementioned and indicated in Fig. 3, whence thesteam passes into another continuously operating sludge separator 61 andthence into a number of headers so labeled,

- through which it reenters the boiler at point 13 in Fig. 1. When thesteam is discharged from the generating chamber at the upper part ofcylindrical coils 5 in Fig. 1, it first enters again a number of sludgevalves 60 as shown in Fig. 3, before the steam is collected from all thecoil groups by a mainheader so labeled in Fig. 3. From this main headerthe steam enters a pressure maintaining valve 35, which is indicated inFig. 3

only in a conventional manner, before it passes through anothercontinuous sludge separator 61 and a number of headers and sub-headersinto the superheater coils shown in Fig. 1 and thus labeled in Fig.3.Before the steam is discharged from the superheater into the conduitthat leads to the-consumers as shown in Fig. 1 it first passes, asindicated in Fig. 3 at 60 again through a number of sludge valves and acontinuous sludge separator 61.

The interposition of such a large number of sludge valves and separatorsis extremely important in this type of tubular boiler on account of thecomparatively small crosssection of the tubes in which evenslightreductions in cross-section by accumulating scale and slud e may havevery undesired and detrimenta results.

In Figs. 4 to 6 I have illustrated in detail one of the forms which thesludge valves 6060 mentioned hereinbefore with reference to Fig. 3, mayassume for practical purposes. Referring to Fig. 4 more articularly, itwill be noted that such a va ve consists of a valve body 40 in thebottom of which a disc .41 is located which is provided with Y a numberof axial borings 42, (in this case 3, see Fig. 6) arranged in a circle,which borings register with similarly arranged passages 43 provided inthe bottom of the easing. To these casing passages 43 are connected theindividual tubes 44 which may come from any of the boiler portions suchas the economizer or the generator or the superheater. As will be notedfrom Figs. 4 and 6 the passages 42 of disc 41 register in this case withthree of the tube passages, so that the tubes 44 connected to thesepassages can freely discharge their contents into the casing space 45which is connected with an outlet 46 to which one of the main conduits47, for instance such as would be employed between the economizer andthe generator, or between the generator and the superheater isconnected. I

Disc 41 is provided besides with an internal passage 48 which terminatesat one end in the bottom center of the disc and at the other end at theperiphery of the same circle on which passages 42 terminate. Thus,passage 48 registers with one of the passages 43 provided in casing 40,for instance in the pres ent case with the passage denoted with 43 inFig. 4, so that the steam discharge through passage 43 into the valvewill not reach the interior 45 of the valve, but will be dischargedthrough a central bottom passage 49 provided in the casing as soon asthe valve 50 connected at this point to the valve casing 'is opened.Thus, any sludge which has col lected in the tube 44 which is connectedto the inlead 43 of the casing will be directly without reaching theinterior of the casing.

Disc 41 is normally raised from its seat as shown in Fig. 5, so that alltubes 44 connected to the valve can freely discharge the operatingmedium into the interior 45 of the valve casing, whence it passes outthrough conduit 47. Disc 41 is raised by means of a valve rod '51 whichis disposed in a screw spindle 52 threaded into a yoke 53 mounted on topof valve casing 40. This screw spindlefcan be operated by a wheel 54.Spindle 51 is prevented from axially shifting in screw spindle 52 bymeans of two pins 55. Vhen valve disc 41 is raised, as shown in Fig. 5,it can be rotated into any position in which its internal passage 48registers with the desired tube to be flushed, and in order to exactlyascertain from the outside the desired tube, valve rod 51 is provided onthe outside with a disc 56 which has holes 57 at its peripherycorresponding in number and angular position with the bottom passages 43of the valve casing. Two diametrically opposite pins 58 are provided ontop of the valve casing by which the disc 56 is engaged when in thedesired angular position. and then the 'valve disc can be lowered ontoits seat for mentioned hereinbefore may be constructedfor instance asshown in Figs. 7 and 8 as fol- I lows. represents a container ofsuitable form in the lateral wall of which terminate the tubes 71 whichcarry the medium from which the sludge is to be continuously removed. Incontainer 70 is arranged in ver tical position, and rather close to theterminals of tubes 71,, a transverse bafile plate 72 unequal volume, inthe, smaller of which 76 the mediumsupply tubes terminate, and the'.larger of which 77, is connected at the top with the medium dischargetube 75, through which the medium collected from all tubes 71 isconducted away. By this arrangement the medium flows downward at highvelocity through the small compartment 76 and, reversing its flowabruptly at the lower end of baffle plate 72, flows upward at lowvelocity through compartment 77. By this sharp diversion of the-flow andits speed reduction thereafter the solid matter contained in the mediumis constantly thrown towards the bottom of the container, whence it canbe continuously drained off through discharge pipe 78.

I claim:

' 1. A vertical boiler having a polygonal outside contour and having avertical combustion chamber, and means for supplying fuel from one ofits ends, the portion of said chamber near the fuel supply havingcylindrical form, and the remainder of the chambustion chamber. andmeans for supplying fuel from one of its ends, the portion of saidchamber near the fuel supply having cylindrical form, and the remainderof the chamher having polygonal form, and steam generating tubesarranged in coils along the walls of both chamber portions'to followrespectively the round and polygonal contour of said chambers, the coilsin said combus- 7 tion chamber being'divided into two main sections, onelocated in the cylindricalportion, the other in the polygonal portion ofthe in the outside contour of the generator, and

being arranged to receive each a portion of the combustion gases fromsaid combustion chamber, the portion of said combustion chamber near thefuel end having substantially cylindrical form and the remainder havingpolygonal form similar to the poly onal generator form, whereby the gasstreams passing from the polygonal chamber portion into the severalconvection chambers are uniformly distributed over the entire width ofthe convection chambers.

4. A steam generator having a combustion chamber, and means forsupplying fuel to it at one of its ends, and at least one convectionchamber arranged to receive the gases from said combustion chamber, bothkinds of chambers containing heat absorbing elements, the portion ofsaid combustion chamber near the fuel supply end having substantiallycylindrical form, and the remainder of said chamber having polygonalform, whereby the gas streams passing from the poly,,- onal combustionchamber portion into the convection chamber are uniformly distributedover the entire width of the convection chamber.

5. A steam generator having a combustion chamber, and means forsupplying fuel to it at one of its ends, and at least one convectionchamber arranged to receive the gases from said combustion chamber, theportion of said combustion chamber near the fuel supply end havingsubstantially cylindrical form, and the remainder of said chamber havingpolygonal form, whereby the gas streams passing from the polygonalcombustion chamber portion into the convection chamber are uniformlydistributed over the entire width of the convection chamber, both ofsaidcombustion chamber portions containing heat absorbing tubes forming thewalllining of said chamber, said convection chamber containingsuperheating tubes.

6. A steam generator having a polygonal outside contour, and having acombustion chamber extending longitudinally through said generator, andmeans for supplying fuel "to said chamber at one of itsends, at leastone convection chamber located outside of the combustion chamber wall,but within the outer. contour of the generator, and extendingsubstantially over the entire length of the combustion chamber and beingconnected to the discharge end of said combustion chamber to receive thecombustion gases, both kinds of chambers containing heat absorbingelements, the portion of the combustion chamber at the fuel supply endhaving substantially cylindrical form, and the remain der havingpolygonal form, the corner spaces formed between said cylindricalchamber portion and the convection chamber having ducts for conveyingcombustion air to the fuel supply end of said combustion chamber.

7. A steam generator having a polygonal outside contour, and having acombustion chamber extending longitudinally through said generator, andmeans for supplying fuel to said chamber at one of its ends, at leastone convection chamber located outside of the combustion chamber wall,but within the outer contour of the generator, and extendingsubstantially over the entire length of the combustion chamber and beingconnected to the discharge end of said combustion chamber to receive thecombustion gases, the portion of the combustion chamber at the fuelsupply end having substantially cylindrical form and the remainder havinpolygonal form, heat absorbing tubes forming the wall lining for theentire combustion chamber, and superheating tubes disposed in saidconvection chamber.

8. A steam generator having -a polygonal outside contour, and having acombustion chamber extending longitudinally through said generator, andmeans for supplying fuel to said chamber at one of its ends, at leastportion of the combustion chamber at the fuel supply endhaving'substantially cylindrical form and the remainder having polygonalform, heat absorbing tubes forming the wall lining for the entirecombustion chamber, and superheating tubes disposed in said convectionchamber in the portion adjacent to the polygonal combustion chamberportion, and an air preheater disposed in the remainder of saidconvection chamber.

9. A tubular steam generator having a rectangular outside contour andhaving a combustion chamber extending in its central portionlongitudinally through the generator, means for supplying fuel to saidchamber at one of its ends, and heat absorbing tubes in said chamberforming a lining for its entire wall, two convection chambers containingsuperheating tubes and being disposed on diametrically opposite sides ofsaid combustion chamber for its entire len h, and being connected to thedischarge en of said combustion chamber to receive the combustion gasestherefrom, the portion of the combustion chamber at the fuel supply endhaving substantially cylindrical form and the remainder havingsubstantially rectangular form, whereby the gas streams passing from thecombustion'chamber into the several convection chambers are uniformlydistributed over the entire width of said convection chambers. MARTIN

